228 LEPIDOPTERA, 



various iiarts of Nortlieru I'airope, witli leeLind, and 

 is said to occur also in North America, iu Elaine and in 

 Oregon. 



5. P. logiaua, Sdiil}. ; tristana, Huh. — Expanse 5 inch 

 (14—16 mm.). Fore wings some shade of brown, with a 

 broad darker costal trinagle before the apex, and a cluster of 

 raised dots, often black, before the middle. 



Antennfe, palpi, head, and thorax brown or purple-brown ; 

 abdomen grey-brown ; anal tuft ochreous. Fore wings short 

 and moderately broad ; costa very strongly arched at the 

 base and a little so throughout ; apex blunt, colour reddish- 

 brown, reddish-grey, purple-brown, yellow-brown, or even 

 white ; a cluster of small raised dots, often black, lies not far 

 from the base ; a very broad flattened triangle extends from 

 the arch of the costa to the apex of the wing, and is either 

 of a darker shade of the ground colour or of some dark con- 

 trasting colour ; very often a distinct black or dark brown 

 dot lies near the base of the dorsal margin ; cilia brown, 

 clouded with red-brown. Hind wings smoky white, with the 

 apical region darker, cilia whitish. Female similar. 



Underside of the fore wings polished leaden-brown ; costa 

 dotted with white. Hind wings leaden-white. 



Variable in colour as already shown, but usually some 

 shade of purple-brown, brown-drab, or red-brown. The most 

 conspicuous and beautiful form has the ground colour of 

 beautiful satiny- or silvery-white, with the costal triangle 

 purple-brown. 



On the wing iu June and July, and as a second and more 

 abundant generation from September to November, and 

 after hybernation in March and April. 



Larva active, rather flattened, the segments deeply 

 divided; head pale yellow, mouth darker; body semi-trans- 

 parent, very pale yellow, with a large distinct dull green or 

 brown internal dorsal vessel ; plates both nearly colourless. 



